1. Field of the Invention
The invention relates to an aerosol generator, in particular a soot generator, and a method for creating an aerosol, in particular a method for creating soot.
2. Description of the Related Art
To reduce particles from the exhaust gas of an engine, particle-reducing components are used, such as filter systems and/or catalytic converters. The filter systems that are used today differ essentially by the type of regeneration (burning off of the soot) they employ. Active regeneration is the term used here for the deliberate burning off of the soot for a limited time and passive regeneration is the term used here for the continuous breakdown of soot, ideally in dynamic equilibrium. For the technical testing of the filtering efficiency or the reactivity of soots, model soots and actual soots are used. At present, various particle measuring techniques, which determine the particle mass and the number of particles, are used for testing the legally limited emission of particles. At present, there are no standardized particle aerosols being used for the validation and calibration of these particle measuring techniques.
Apart from internal combustion engines, currently various soot generators are used for producing soot particles.
EP 0 353 746 A2 describes a device that creates soot particles by a spark discharge at graphite electrodes. U.S. Pat. No. 4,751,069 A describes a system for creating soot particles by cracking carbon-containing materials at high temperatures. EP 1 055 877 B1 describes a burner for creating soot particles that burns a combustible gas and an oxidizing gas in a combustion chamber. A refinement of this burner is described in EP 1 590 408 B1. A further refinement is described in WO 2014/085941 A1, which describes the use of a liquid fuel for creating soot particles.
A disadvantage of the known devices is that the chemical composition of the particles and also the particle morphology, i.e. the size and nature of the particles created of the aerosol, cannot be influenced, or influenced only to a limited extent.